The River Murray has peaked in all affected South Australian towns, authorities say.
SA's Emergency Services Minister Joe Szakacs said the peak reached Wellington, close to where the river meets Lake Alexandrina, on Wednesday.
"The peak has now reached every town in South Australia that will be affected by these floods," he said.
Mr Szakacs said the levees created by authorities along the river to protect towns and properties have "done their job", although acknowledged others have experienced breaches.
"We're not out of the woods yet," he said.
"These levees are still engaged. They're still doing their job by holding back these floodwaters."
Mr Szakacs said flows across the border were now at 135 gigalitres.
"That has been a marked decrease from the peak of just over 190 gigalitres just a short number of weeks ago," he said.
The State Emergency Service's Chris Beattie said the river peaked at Mannum on January 7 and Murray Bridge on January 9.
He said peak flows were "well and truly within Lake Alexandrina now" and will start to flow out through the Murray Mouth over the coming days.
"In terms of the wind and the storm front coming through on the weekend, we would expect some low-lying properties to see some wave action against them, particularly in and around Milang, but also we're keeping a close eye on Princes Highway north of Meningie," he said.
Mr Beattie said flows were expected to drop to 60 gigalitres per day at the border by the end of January.
Mr Beattie said there had been just over 3,500 power disconnections to date, below the expected number of 4,000.
"We've pretty much seen the last of the planned power disconnections ... any further disconnections are likely to be as a result of any over topping or breaching of any further levees," he said.
Meanwhile, recreational cockle fishing on South Australia's Fleurieu Peninsula will be closed until further notice.
The Department of Primary Industries said the "precautionary measure" was made due to the detection of E.coli in pipis in levels above what is considered safe for human consumption.
The closure includes the entire Goolwa Beach from the Murray Mouth to Middleton Point.
